Mechanical pencil



A. POLLAK MECHANICAL PENCIL Aug. 13, 1929.

Filed Jan. 20, 1.927 2 Sheets-Sheet ATTORNEY INVENTOR iw/Mw FQMA/r nih.-

Aug. 13, l929.v. A. PoLLAK MECHANICAL PENCIL Filed Jan. 2o. 1927 2 sheets-smet 2 a Il dv a/VMMH ML f,// WwW/w MM 8 ATTORNEY.

Patent 13, i929.

A1535. iz i. f POLLAK, OF FAR ROCKAWAY, NEW YORK, ASSIGNOR TO PENCIL MECHA- -NISM CORPORATION, F NEW YORK, N. Y., 'A CORPORATION NEW YORK.

ancnariroar. ramera.

Application filed January 20, 1927.

This invention relates to improvements in mechanical pencils, preferably of the mag'- azine type.

Among the objects of thls invention are` to simplify the'\ construction of pencils of this type and to enable the manufuacture thereof more economically; to provide a pencil construction that can be readily and easily repaired and that can be assembled and disassembled by' unskilled persons wlthout the use of tools; to provide in a retillable or vmechanical lead pencil, feeding lmechanism preferably embodying a- 'gripping element composed of a plurality of fulcrurned grlpping members Afor Vmoving a lead of small diameter in a step-by step movement through the feed chanriel or pencll-bore withoutnlcking or breaking the same; to provideteeding mechanism whereby the lead will be positively gripped with a resilient pressure and any crushing or indentation of the lead will be avoided; to provide `lead-:feeding mechanism having a lead-gripping element embodying a plurality of longitudinally split lead-encircling members preferably provided with arcuate lead-gripping surfaces arranged to close in parallel relationship to each other and thus ito avoid unbalanced pressure on and breakage of the lead, while 3o procuring a positive engagement and gripping thereof; to provide a pencil construction in which the feeding of the lead is accomplished through rictional engagement of a resilient closing member with the leadgripping element and manual feeding pressure is applied to this gripping element through said closing element; to provide a mechanical. pencil with reciprocating feeding mechanism operable to have at one end of its reciprocating movement aquick and positive lead-gripping movementas opposedv to a gradual lead-gripping movement and a. positive and quick release oflthe gripping member at the other end thereof, thus avoiding lost motion and avoiding the carrying back or recessional movement ot the lead by the feeding mechanism, and consequently enabling a complete feeding movement or the lead-on each reciprocating operation of the feeding mechanism; to provide, in a mechanical pencil, a lead magazine having a reciprocating bottom portion preferably of plunger-like conformation, adapted to agi- Serial No. 162,272.

tate the lead. in the magazine and thus to cause a more positive guiding and feeding of the leadfrom the magazine into the feed channel o r bore of the pencil; to provide a pencil construction in which a lead-gripping element is mounted to have a limited float-- ing movement within the pencil casing and a resilient closing element is movable automatically by a spring to carry the gripping element to one limit of its movement vand then to resiliently engage said gripping element to cause a gripping thereby of the lead L and a frictional locking engagement sutli- Acient to permit a manual lead-feeding moveas to co-actV and cooperate with each other in the performance of the functions and the accomplishment of the results herein con- Vtemplated, and comprises kin on'eof its adaptations the spjecies or preferred form illustrated in the accompanying drawings, in which l Fig. l is alongitudinal section of a pencil embodying my invention;

Fig. 2 is an enlarged section similar to Fig. l of the lower portion of the pencil, showing the parts of the feeding mechanism in initial lead-gripping position;

Fig. 3 is a-view similar to Fig. 2 showing the feeding mechanism with the parts depressed just prior to release of the lead by the gripping element;

Fig. i is a longitudinal section similar to Figs. 2 and 3, showing the parts of the feeding mechanism further depressed to completely releasethe gripping element from the lead;

Figs. 5 to 8 are a series of cross sections on the lines 5 5, 6 6, 7 7, and 8 8 respectively of Fig. 2, loohng in the direction of the arrows;

Fig. 9 is a view, in elevation, of the lower portion of the operating tube removed from the casing and sectioned to show the gripping and closing members of the feed mechanism;

Fig. 10 is a perspective view of the agitating bottom portion of the magazine section; and

Fig. 11 is a perspective view of the internal surface of the lead-gripping element of my feed mechanism.

Referring now to these drawings, which illustrate a preferred embodiment of my invention, C indicates an outer casing having at its lower end a tapered tip c which, as shown, is connected to the casing@ by interengaging screw-threads t. Said tip o has at its lower end a lead channel or bore b of substantially the diameter of the leads to be used, which communicates with a bore ZJ of increased diameter, which in turn communicates with a casing bore B of still greater diameter.

Mounted in stationary position within the bore of the tip c, I preferably provide a lead-guiding tube 1 having a bo-reregistering with the bore 1a and provided at its lower end with a split portion adapted to provide resilient lead-guiding jaws 2- surrounding said bore l, having an upper portion 1b projecting upwardly into the casingboreB and provided with a sharpened or tapered end 1c arranged as hereinafter described to act as an opening element for the lead-,gripping elementy of the feed mechanism.

Mounted within the casing-bore B above the opening and guiding element 1, I provide lead-feeding mechanism for moving the lead in a step by step movement through the channel or lead bore 1a in the guiding member 1 and through the bore Z2 in the lower end of thetip portion of the casing C, said feeding mechanism being adapted to so feed a lead of small diameter without nicking or breaking the same. It is obvious that in feeding leads of small diameter a relatively large surface of the lead, both circumferentially and longitudinally should be gripped, and it will be understood that space within the bore of a pencil is extremely limited and the gripping element must be relatively small. In order to provide a gripping element of the required small size which will act quickly and positively to grip and release the lead, which will have the necessary accuracy with which this part must be formed, 'and which may be readily and quickly assembled, both initially and for repairs, I have provided a gripping element composed of a plurality of parts fulcrumed to swing or rock from gripping to non-gripping positions and vice versa upon reciproeating movement of such elementand, as shown, I provide a gripping element 10 composed of two semi-cylindrical parts 10', 1()a and having semi-cylindrical gripping surfaces 10e and I mount said two cylindrical parts on a fulcrum suitably guided within the casing. As illustrated, a guiding member 12 carries at its lower end a depending fulcrumI portion 15 which extends into a split bore l()b formed between the parts 10', 10a. Said fulcrumportion 15 is provided at its lower end with a fulcrum 15 which seats in a fulcrum-seat 10c at the lower end of the bore 10" of said parts 10', 10a, said bore 10b embracing the fulcrum portion 15, (see particularly Figs. 10 and 11), and said guiding member and fulcrum portion are provided with a continuous axial lead-channel or bore 13 communicating at its upper end with a magazine section 14 as hereinafter described, and at its lower end with a middle bore 1.0'1 of reduced diameter, which is again reduced to form the lead-gripping surfaces 10e. lIhese surfaces 10e may, if desired, be roughened or provided with teeth so as to procure a better grip on the leads L as they pass through the continuous bore 13 from the magazine to the bores 10d and 10's of the gripping element 10. The gripping element is thus composed of two semi-cylindrical parts 10', 10, having semi-cylindrical gripping surfaces 10e, and the said two cylindrical parts 10', 10a are mounted on the plunger member 12 to swing about the fulcrum 15 so as to enable contact with and release from the leads L, it being understood that the upper end of the guiding member 12 forms the bottom of the magazine sectionA and this upper end is provided with a depressed conical l surface 13a leading to theibore 13 which in turn communicates at its other end with the middle bore-10b of the gripping member.

This floating gripping element 10 is, in accordance with my invention, recip'rocated and actuated to grip and release thelead, and preferablythe lead will be positively gripped with a resilient pressure which will avoid any crushingi or indentation thereof, and, to this end, my -improvedv mechanism is caused at one end of its reciprocating movement to have a quick and positive lead-gripping movement, while at the other end of its reciprocating movement, this resilient grip will be instantaneously released, thus causing a feeding movement of the lead which will be complete, without any recession of the lead. In the preferred embodiment of my invention shown, the two parts 10', l()a of the lead-gripping element are preferably held together by a band 11 which is preferably formed of resilient wire fitting into grooves 118 in the perimeter of the gripping element 10. f Said gripping element 10 is preferably mounted on the guiding member 12, as above described, to' have a limited floating movement therewith within the bore B of the casing and, as illustratmamie ed, said floating element 12 is of plungerlike construction having its upper end arranged to close and form a bottom for the magazine compartment 13 formed at the upper end of the 'tube 14. The element 12 is guided in its iioating movement by the provision of oppositely-extending guide lugs 12 and 12a extending within oppositely-disposed slots 14, 14a in an'inner actuating tube 14, the upward movement of said'element 12 and that of the'gripping element carried thereby, being limited by enga ement thereof with the lower'end 19 o a relatively stationary outer tube 19 mounted within the casing C.

The gripping element 10 is thus guided and floats with its guiding member 12 within the bore 14b ofthe actuating tube 14. Saidtube 14 preferably has a closing element 16 releasably connected thereto at its lower end. This is accomplished by the provision on said tube 14 of integral lugs 14c fitting into a groove 16 in said closing element 16, the connection being covered by a collar 16a. Said closing element 16 has at its lower end a spring-guiding hub 161. Said closing element 16 is also provided with upwardly-directed resilient arms 17 adapted to encircle the lower end of the gripping element 10 and to move the same inwardly by spring pressure when these resilient split arms 17 are moved upward. As illustrated, the arms 17 are provided with internally-tapered guiding surfaces 17 which are arranged to contact `with the externally-tapered surfaces 10f at the lower end of the ripping element 10. In the preferred em odimentv shown, the upward stroke of the longitudinal reciprocating movement initially moves the element 10 to its uppermost limit of movement and power for this purpose is provided by means of a spring 18 `arranged to encircle the lead-guiding member 1 and to abut at one end against the bottom of the whore B and at the other end against the lower end of the closing element 16 which is connected, as aforesaid,

to the tube 14. rlhe pressure of the spring 18, thus acting through the closing element 16' having the spring arms 17, forces the gripping element 10 and plunger` 12 up to their uppermost limit of movement, which upward movement, as aforesaid, is limited by contact nwith the lower end 19 of the outer tube 19. rllhe gripping element is thus carried upwardly in open position, the spring 11 keeping the parts open until this upper limit of its noating movement is reached, no closing or gripping action taking place during such movement, but when such upward limit of movement of the gripping element is reached, the spring 18 continues to move the closing element 16 upwardly until the resilient arms 17 engage and apply resilient pressure radially on t e lower end of the said gripping clement 10, thus forcing the lead-gripping surfaces '10e into firm though resilient contact with the lead. lt will be seen thatv this closing movement takes place only after the floating gripping element is carried upwardly to its full limit of reciprocating or longitudinal movement; that the movement is purely radial without any accompanying longitudinal movement and can, therefore, have no retracting or recessional effect on the lead, and it will also be seen that the members 10, 10ai of the gripping element are rocked on the fulcrum and close in parallel relationship to each other to cause uniform though resilient gripping pressure on the lead.

' lt will be noted, furthermore, that when 'the closing element 16 so engages the gripping element 10, a frictional contact therebetween will be made which willenable a feeding of the lead by a manual movement of said frictionally-engaged closing element and in the preferred embodiment shown, l procure a feeding of the lead by manual pressure on the tube 14 applied at its upper 4 end. This may be accomplished in any wellknown wayand, as shown, the tube 14 is provided at its upper end with a lead-receiving cup 2() over which is fitted a cap 21. A collar 20- at the lower end of the cup 20 is arranged above an enlarged threaded collar C having a screw-threaded connection at C2 f with the casing, and the tube 14 reciprocates through the bore 20a of this collar C.

rlhe lead being gripped, as aforesaid, manual pressure on the, cap will be transmitted through the cup' 20 and the tube 14 against the pressure of the spring 18, and through the frictional engagement, as 'aforesaid, of theresilient arms 17 with the gripping element 10, the lead may be fed downwardly in the lead-bore or channel through the various elements. ,The longitudinal or reciprocating manual movement of the crippin element so embraced and held in closed lea -gripping position by the arms 17, is limited by direct contact thereof with the upper end 1c of the guiding tube 1, and release of the lead is thus effected after longitudinal movement of the gripping element and the consequent feeding movement of the lead has completely stopped. rlhere, is therefore, no additional feeding movement of the lead, however slight, .during the opening movement of the gripping element, complete o ening of the grippingl element to release the lead being effected by the further or additional releasing movement of the closing element. Ff-he extent of the feeding movement will thus be positively vdefined and limited at opposite ends because .such movement of the feeding element is directly limited before any closing or opening takes place, both gripping and release of the lead being accomplished by the continuance of the stroke of the closing element beyond opposite ends of the stroke of the lead-gripping element.

- As shown, the outer surface of this tube l forms a guide on which the closing member 16 is mounted to reciprocate, said tube, as shown, passing through a bore 16c of said member 16 and engaging the gripping ele:

ment to limit its stroke, and further manual pressure applied through the tube 14 on the element 16 against the pressure of the spring 18, will cause an. additional movement of said closing member and will release the spring arms 17 of the closing element 16 from engagement with the gripping element 10. The position of the parts are such that immediately upon the limiting or stopping engagement of the gripping element, the pointed or tapered end 1 of the limiting stopthereof will force open the jaws and fully release the lead as illustrated in Fig. 4, this insertion of the tapered'end 1 occurring immediately after the release of the gripping member from engagement by the additional downward movement of the closing member 16, Upon release of the manual pressure, the spring 18 will immediately act to restore the parts to their initial position hereinabove described, the floating gripping element 10 and plunger' member l2 being pushed upwardly by the springpressed closing member 16 until such floating members reach their upwardlimit oi movement upon the engagement of the guide lugs 12, 12EL with the lower end 19 of the tube 19, whereupon the closing member hav- Iing a longer stroke also in the upward movement will cause the members 10', 1()a to be swung by the action of the spring arms 17 on the fulcrum 15 to fully close on the lead, said resilient arms 17 moving into the position shown in Fig. 2, so as to provide a frictional engagement with the lower end of said gripping element, as aforesaid.

The operation of the device and its several parts will be clear from` the foregoing description.

Having described my invention, I claim 1. A mechanical lead pencil embodying a casing having at its lower end a tapered tip provided with a lead channel, a lead-gripping element mounted to reciprocate within the casing and composed of a plurality ofmembers rockable on a fulcrum also mounted within said casing, and means for rocking said members on the said fulcrum at oppositeends of said reciprocating movement to alternately grip and release the lead to feed the same in a stepv by step movement through said lead channel.

2.. A mechanical lead ypencil embodying a casing havingat its lower end a tapered tip provided with a lead channel, a lead-gripping element mounted to reciprocate within the casing and composed of a plurality of members rockable on a fulcrum also mounted within said casing to reciprocate with said gripping ement and means for rocking said members on the said fulcrum at opposite ends of'said reciprocating movement to alternately grip and release the lead to feed the same in a step by step movement through said lead channel.

3. A mechanical lead pencil embodying a casing having at its lower end a tapered tip. provided with a lead channel, a member mounted to reciprocate within said casing and provided with a fulcrum, a lead-gripping element reciprocable with said fulcrum member and composed of a plurality of members -r'ockable on said fulcrum, and means for causing the rocking of said gripping members on said fulcrum at opposite ends of said reciprocating movement to alternately grip and release the lead to feed the same in a step by step movement through vsaid lead channel.

4. A mechanical lead pencil embodying a casing having at its lower end a tapered tip provided with a lead channel, a lead-gripping element mounted to reciprocate within the casing and composed of "a plurality of members rockable on a fulcrum also mounted within said casing, a closing element for rocking said members on said fulcrum to close at one end of said reciprocating move-- ment, means for moving said two gripping and closing elements together in an engaged lead-feeding movement, and means for stopping the movement of one of said elements before the other to release the lead.

5. A mechanical lead pencil embodying a casing having at its lower end a tapered tip provided with a lead channel, a lead-grip.- ping element mounted to reciprocate within the casing and composed of a plurality of members rockable on a fulcrum also mounted within said casing, a closing element having a plurality of resilientarms for rocking said members ensaid fulcrum to close at one end of said reciprocating movement, means for moving said two gripping and closing elements together in an engaged lead-feeding movement, and means for limiting the movement of the gripping element to a shorter stroke thanthe closing element to release the lead.

6. A mechanical lead pencil as claimed in claim 5, in which the resilient closing element is movable by spring pressure into frictional engagement with said gripping element and means is provided for exerting manual pressure on the closing element to reciprocate the closing and. gripping elements together `to move the lead and feed it through the tip. f

u 7. In a mechanical lead pencil casing having a centrally-disposed lead channel and an enlarged magazine section above `said magazine section having a movable bottom portion provided with a depressed tapered surface for guiding the ends of units of lead toward said centrally-disposed lead channel, feeding means-for the lead connected with said movable bottom, whereby the lead in said magazine sect-ion will be agitated to enter said lead channel, saidinovable bottom portion having a fulcrum, a gripping element having a plurality of gripping members mounted to rock on said ulcrum, means for opening and closing said gripping members to grip and release the lead upon reciprocating movement thereof, and means for reciprocating said members to feed the lead through the lead channel in a step by step movement andi also to agitate leads in the magazine section.

8. A mechanical lead pencil embodying a casing having at its lower end a tapered tip provided with a lead channel, a gripping element mounted to reciprocate within said casing and having a plurality of movable members adapted to close against the units of lead, and a closing element provided with a plurality of resilient arms arranged to close over the members of said gripping element to produce a resilient grip on the lead, means for slidably moving said gripping and closing elements together in an interengaged lead-feeding movement, and means for releasing said resilient closing member from \the gripping element to release the lead.

In witness whereof, I have signed my name to the foregoing speciiication.

ABRAHAM POLLAK. 

